Al-Qaeda suspects questioned

The arrests followed operations in France and the UK

Spanish authorities are questioning 16 men arrested in a police swoop on suspected al-Qaeda-linked militant cells on Friday.

Experts are examining explosives and chemicals seized in the raid.

Prime Minister Jose Maria Aznar said a "major terrorist attack", had been thwarted by the arrests in the north-eastern Catalonia region.

Mr Aznar described the arrests as an extraordinarily important strike in the war against terror.

'Real threat'

"I want to highlight once again that when we talk about the fight against terrorism and the circles around it and when we talk about ensuring the safety and the peace of all, we are not talking about fantasies," he said.

More than 150 anti-terrorist police agents took part in Friday's pre-dawn swoop against the suspected al-Qaeda cells in more than a dozen apartments in Barcelona and elsewhere in Catalonia.

Suspicious resins, fuels and other chemicals are being examined, along with electronic equipment, detonators and remote controls for use in bomb-making.

Bomb-making components were seized in the raids

The arrests came two days after an operation in Italy to arrest five Moroccans on charges of illegal possession of explosives.

The BBC's security correspondent Frank Gardner said there had been an unprecedented level of co-operation between the intelligence services of several European countries including Britain's MI6.

French and UK links

Mr Aznar said those arrested had links to Algerian militant groups.

"[The police] have broken up a major terrorist network... linked in this case to the Algerian Salafist group, a splinter of the Armed Islamic Group (GIA), which has clear connections with the criminal organisation of Bin Laden," he said.

The dismantled network has connections with terrorists arrested recently in France and Britain who were preparing to carry out attacks, using explosives and chemical materials

Prime Minister Aznar

Interior Minister Angel Acebes said the suspects were divided into two groups, both led by Algerians.

A suspect named as Mohamad Tahraqui was said to be in charge of the Barcelona-based group, while the other operated out of Banolas in neighbouring Gerona province under the leadership of a man named as Bard Eddin Ferdji.

The raids took place after a lengthy investigation assisted by the French and British authorities.

A UK investigation into terrorist cells, sparked by the discovery of the poison ricin in London, has unearthed a huge number of suspects all over Europe.

Al-Qaeda meetings

Over the course of the past year, Spain has arrested about 20 people thought to have links with the militant Islamic organisation.

However, many of these have been released on bail because of lack of evidence.

Several of the arrests have taken place in Catalonia, which has a large immigrant population from North Africa, the Middle East and South Asia.

Spain is thought to have hosted a number of important meetings by top al-Qaeda operatives in the run-up to the 11 September attacks on the United States.

Mohammed Atta, who led the attacks, is known to have visited Spain twice in the months leading up to them.